Regenerative repeater for start-stop systems of automatic telegraphy



May 3, 1932. R. F. DIRKES ET AL 1,355,935

STQP SYSTEMS OF AUTOMATIC TELEGRAPHY Filed May 16, 1930REGENERATIVE'REPEATER FOR START:-

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M n I 3 NM. on mm w w May 3, 1932. R. F. DIRKES ETAL REGENERATIVEREEEAI'ER FOR START-STOP SYSTEMS OF AUTOMATIC TELEGRAPH! Filed May 16,1950 3 Sheets-Sheet 2 -& r u "3 x: k m 5* l S i n5 wfim 8% x L JS 0 e 5w Q 5% Q mentors;

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REGENERATIVB REPEATER FOR START-STOP SYSTEMS OF AUTOMATIC TELEGRAPH!Filed ua Te, 19:50 5 Sheets-Sheet 3 inventors.-

,Z I. flirkes ,A nderson, Jr

Gttomeg Patented May 3, 1932 iJNrrsu stares PATENT OFFICE ROBERT F.DIRKES, OF JAMAICA, NEW YORK, AND JAMES N. ANDERSON, 53., OF NORTH;

PLAINFIELD, NEW JERSEY, ,ASSIGNORS TO THE WESTERN UNION TELEGRAIH COM-PANY, OF YORK, N. Y., CORPORATION OF NEW YORK REGENERATIVE BEIEA'IER FORSTART-STOP SYSTEMS OF AUTOMATIC TELEGRAPHY Application filed; May 1 9Serial No.

This invention relates to a start-stop telegraph system and moreparticularly to regenerative repeaters therefor.

As is well known to those skilled in the art of telegraphy, repeatersmay be divided into two general classes, those which provide a strongerimpulse on retransmission, and those which perform that function and inaddition provide a reshaping of distorted impulses on retransmission.This invention relates to the latter type of repeater.

The regenerative principle of operation has been applied extensively tomultiplex telegraph systems but has never been applied to start-stoptelegraph systems. 7

Accordingly the main object of the present invention is to provide astart-stop apparatus employing the regenerative principle of operation.

Repeat-er stations often function as the originating point of signallingimpulses for communication therebetween and either ter minal station.lVhen used as a repeater,

. impulses are received and stored up in'a set of relays at theintermediate or repeater station to be retransmitted as regeneratedimpulses. By means of a switching arrangement, the transmittingequipment can be substituted for the receiving portion of therepeaterapparatus.

Accordingly, another object of this inven tion is to providearegenerative repeater that may be converted into a transmitting'set.

In start-stop systems, difiiculty has been experienced in maintainingsynchronismbe' tween the receiving distributor and thetransmittingdistributor operating at a high speed due to vibration of the brushes atthe stop segments when completing the circuit for the'starting magnet.As is wel'l'known, the circuit for the starting magnet extends throughthe brushes of the receiving distribu:

tor and start segment. In order'to' insure synchronism between thetransmitting and receiving distributor, the receiving mantator brushmust be rotated slightly faster than a the transmitting distributorbrush so that 7 the brush at the receiving'end will reach the startsegment and beprepared to receive the start impulse when it arrives. Itwill be obvious that in coming to rest after rotating at a hi h speed,the receiving distributor brush will undergo a certain amount ofchatteringv or bouncing Consequently when the start brush vibrationisconsiderable, the brush may be thrown completely out of phase with.

the incoming signal. The present invention aims to overcome this"difliculty by .provid-- ing an auxiliary multiple circuit for the startmagnet. which circuit is entirely independent of the distributor brushfor insuring the .1

positive energiz'ation of the starting magnet when the start impulseisreceived. a p

A further object of the presentlinvention, therefore, is to providemeansfor assuring the maintenance of synchronism in a start stop system, rThe invention-may reference to the following description-in .connectionwith the accompanying drawings in which r I Figurel is an elevationalview showing the distributors and'c'ommutator' and the power drivetherefor, I Y

Figure Qfis a diagrammatic illustration of the apparatus embodying theinvention arranged to operate as a repeater,- and Figure 3 is adiagrammatic illustration of the apparatus arranged to operate as atransmitter. I

receiving distributor S2, transmitting dis tributor 38'andcommuntator'34 The motor 31:drive's the main shaft 85 having a worm36'fixedthereon in mesh with aworm gear be best understood byReferring-to Figure 1 the repeater com prises an'electric' motor 31 foroperat ngthe.

37 carried on shaft 38. Connected to the shaft 38 through frictionclutches to be described hereinafter are the receiving distributor 32and transmitting distributor 33. The receiving distributor 32 comprisesa brush arm 40 carrying four brushes 41, 42, 43, and 44 which wipe overrings 45, 46, 47, 48, respectively, as the arm 40 rotates. Ring 45comprises a rest-start segment and six code segments. Ring 46 is solid,ring 47 comprises three segments and ring 48 comprises four segments.The starting and stopping of the rotation of the arm 40 is controlled bya starting magnet 50 having an armature 51, pivoted at52, and, normallyheld in retracted position by a spring not shown. The armature isprovided with a stop lug 53 which liesin the path of the arm 40 when themagnet 50 is de-energized and the armature is in retracted position.Energization of the magnet 50 attracts armature 51 so that the stop lug53 moves out of the path of rotation of the arm 40 and the arm 40 ispermitted to start rotating.

The transmitting distributor 33' comprises a rotatable brush arm 55carrying two brushes 56 and 57 which wipe over rings 58 and 59respectively, the former comprising a start segment,"a plurality of codesegments and a rest segment, the latter being a solid ring. As in thecase of the receiving distributor, the transmitting distributor isprovided with a starting magnet .60 which has an armature 61 pivoted at62 normally held in retracted position by a spring not shown andprovided with a stop lug 63. The magnet controls the starting of thetransmitting distributor arm 55 in the same manner that the magnet 50controls the starting of the distributor arm 40. y

The frictional clutch for connecting the brush arms and 55 with theshaft 38 is well known in the art but will be described briefly herein.The friction clutch comprises two metal discs 64 and 65 which aresecured to the shaft 38. Between the metal discs 64 and 65 aretwofriction discs, 66 and 67 made of suitable friction material andarranged between these friction discs is the brush arm 40. As the shaft38 rotates, the metal discs 64 and 65 rotate therewith. If the arm 40 isfree to rotate, the frictional forces acting through the friction discs66 and 67 will be sufficient to rotate the arm. If the magnet 50 isde-energized the lug 53 of armature 51 willprevent the rotation of'brusharm 40 but the friction clutch will be continuously operating ready torotate the arm 40 as soon as'it is released by energization of magnet50. Geared to the main drive shaft 35,

other and each section comprising a short conducting segment and aportion of insulating material. The conducting segments are designatedin the drawings by reference numerals 72 to 76, inclusive. Cooperatingwith each of the sections is a pair of brushes. These brushes aredesignated in the drawings by the reference numerals 77 to 86 inclusive.

The arrangement of the apparatus for op eration as a regenerativerepeater is shown in Figure 2 in which the distributor rings have beenshown developed for the sake of clearness. As shown, the apparatuscomprises in addition to the distributors and the starting magnets, areceiving relay 87 which is responsive to the incoming impulses from theremote station over line L, a starting relay 88 which controls amultiple circuit around the brushes 41 and 42 for insuring the properoperation of the start magnet 50 in a manner to be describedhereinafter, a transmitting relay 89 which controls the transmission ofthe impulses to a ticker or printer or to a remotestation, and a groupof six polar relays 90 to 95, inclusive. These relays are known in theart as Potts relays, and, as is well known to persons skilledin the art,the armature of such a relay remains operated in whichever position itis thrown.

. As impulses are received over the signalling line from the remotestation by the receiving relay 87, its armature 96 vibrates betweencontacts 97 and 98. Contact 97 is connected to positive battery andcontact 98 is connected to negative battery. The armature 96 isconnected over a conductor 99 to the solid ring 46 of the receivingdistributor 32. Thus the position of the armature 96 of relay 87determines the polarity that is applied to the ring 46. Armature 96 ofthe relay 87 is connected over a conductor 100 to the contact 101 of therelay 88, and the armature 102 of the relay 88 isconnected over aconductor 103 with the start segment of ring 45. This segment isconnected over a conductor 104 with one terminal of the winding of startmagnet 50, the other terminal of the Winding being connected to negativebattery. When the armature 102 of the starting relay 88 is in engagementwith contact 101, the circuit comprising conductors 100 and 103constitutes an auxiliary energizingcircuit' for the receiving startmagnet 50, as will be described hereinafter.

The winding of the starting relay. 88 has one of its terminals connectedto ground and the other terminal connected over a conductor 105 tosegments 13 and 14 of the ring 47. When brushes 43 and 44 are engagedwith the segments 13 and 15, respectively, negative battery will beextended over segment 15, brush 44, brush 43, segment 13, conductor 105,winding ofrelay 88 to ground. Negative current flowing through thewinding of relay 88 operates armature 102 into engagement with contact101and thereby closing the auxiliary circuit including theconductors 100and 103.

lVhen the brush 44 moves off the segment 15 a circuit is establishedfrom positive battery over segment 16, brushes 44 and43, segment 13,conductor 105, and winding of relay 88 to ground. Positive currentflowing through the winding of relay 88, operates armature 102 intoengagement with contact 106 thereby breaking the auxiliary circuit.

The receiving brush 41 initially is resting on the rest-start segment ofring 45.. At this time the brushes 43 and 44 are respectively inengagement with the segments 13 and 15, and the brush 56 of thetransmitting distributor is on the rest segment of the ring 58. To startthe apparatus a positive impulse is required. WVhen such impulse isreceived by relay 87, armature 96 will be, operated into engagement withits contact 97 thus extending positive battery over contact 97, armature96, c0nductor 99, solid ring 46, brushes 42 and 41, rest-start segmentof the ring 45, conductor 104 and through the winding of the receivingstart magnet 50 to the negative battery. The magnet 50 energizes andremoves its armature 51 (Figure 1) from the path of the brush arm 40,allowing the brush arm to rotate. The speed of rotation of the arm is 50adjusted that as each impulse comprising the code combinationrepresenting a character is received on the receiving relay 87, thebrush 41 will be wiping over the segment on the ring 45 corresponding tothe position of the impulse in the code combination.

As the brush 41 wipes over the succeeding isegments 1 to 6, inclusive,the polar relays 90 to 95, inclusive, are energized by positive currentsor negative currents depending upon the polarity of the incomingimpulses, and the armatures of the polar relays are thrown to the rightor left. It is to be noted that when the brush 41 moves off therest-start segment of ring 45, the primary energizing circuit for thestart magnet is broken and the magnet 50 is'deenergized, allowing itsan; mature 51 to move into the path of thebrush arm 40 sothat the brusharm will be stopped.

ing through the winding of relay 88 moves its armature 102 intoengagement with contact 106 thereby breaking the auxiliary circuit formagnet 50. hen the brushes 43 and 44wipe over the segments 11 and 12,respectively, a

icircuit is established for the sending start magnet from positivebattery over segment 12, brushes 44 and 43,-segment 11, GO11 ductor 107and through the winding of magnet 60 to ground. Magnet 60 energizes and:

moves its armature 61, (Figurel) outv ofthe.

when brush4l wiped over segment 1. This provides the necessary overlap.

The startsegment on ring 58is permanently connected to positive battery.Ascordingly, when brush 56 wipes over the start segment on ring 58 apositive impulse will be extended from the start segment over brush 56,brush 57, ring 59, conductor 108 and through the winding ofthetransmitting relay -89. to ground. Positive current flowing through thewinding of transmitting relay 89 moves its armature 109 into engagementwith contact 110 extending a positive impulse from positive batteryover. contact 110, armature 109 and overa conductor 111 to a stockticker or. printer, Vv hen brush 56 wipes over the segment 1 of ring 58,the impulse pre' viously stored in relay will be extended over brushes56 and 57, ring 59 and conductor 108 to the transmitting relay 89,whichin turn will operate its armature in accordance with the polarity of thepotential to extend a corresponding impulse over the. conductor 111. Ina similar manner, as the brush 56 wipes over the segments 2, 3, 4, 5 and6, the impulses previously stored in the polar relays, 91 to 95,inclusive, are extended to the transmittingrelay 89. 3 There is thusprovided an overlap whereby impulses are being stored in the polarrelays 90 to and subsequently transmitted by the transmitting'dis:tributor. I i s 3 The restsegment of the ring 58 is permanentlyconnected to negative battery. Ac cordingly, when the brush 56reachesthe rest segment a negative impulse will be transmitted over theconductor 108 and through the transmission relay 89 and over the line111.

Itwill be. noted thatthe rest segment of the ring 58 is shorter than'theother segments in ring 58. The purpose of this proricvision is toassurethe stopping of the brush.

56 each time onthe rest segment and thereby assuringthestarting of thebrushes in a positive manner by actuation of the starting magnet 60. Itis understood that the combined time of movement and rest of the brush56 onthe rest segment is the same as the time required in the movementof the brush 56' made for an eight-unit code, it is of course,

obvious that the principle herein described embodiment of the inventionlllustrated, provision has been spectively.

segment lot ring 45 the first impulse of the code representing thecharacter Y 1s TSCGlVGd.

may be applied to any of the accepted forms of start-stop telegraphy.The eight units for one character combination are as follows: start,selection 1, selection 2, selection 3, selection4, selection 5,selection 6 and rest.

The operation of the repeater will now be described, assuming that thecharacter Y is to be repeated. The character Y consists of alternatepositive and negative impulses. The brush 41 is resting on therest-start segment of ring 45, and the local brush 43 is resting onsegment 130i the ring 47 as shown in Figure 2. 'lVith the parts in thisposition, negative battery is applied to the coils of receiving relay 87and its armature 96 is in engagement with the contact 98. The firstimpulse to be received isthe start impulse which is of positivepolarity. The armature 96 of receiving relay 87 will therefore be thrownto the contact 97 extending posi tive battery over: conductor 99, ring46, brushes 42 and 41, rest-start segment of ring 45, conductor 104 andthrough the winding of receiving start magnet 50 to negative battery.Start magnet 50 is energized releasing the brush arm 40 for rotation.Brush arm 40 as it rotates moves the brushes 41, 42, 43 and 44 over therings 45, 46, 47 and 48, re-

As the brush 41 wipes over the by the relay 87. This impulse is negativeand moves armature 96 of relay 87 into engagement with contact 98extending negative battery over contact 98, armature'96, conductor 99,ring 46, brush 42, brush 41, segment 1 and through the winding of polarrelay 90 to ground. Negative current flowing through the winding ofpolar relay 90 moves its armature into engagement with contact 115thereby extending negative battery from contact 115 over the armature ofpolar relay 90 to segment 1 of the transmitting ring 58.

When the brush 41 wipes over the segment 2 of ring 45 the second impulsein the code combination representing the character Y is received byrelay 87. This second impulse is positive and energizes the receivingrelay 87 to move its armature 96 into engagement with contact 97extending positive battery from contact 97 over armature 96, conductor99, ring 46, brush 42, brush 41, segment 2, winding of polar relay 91 toground. Positive current flowing through winding of polar relay 91causes its armature to be thrown to the left into engagement withcontact 116, extending positive battery from contact 116 over thearmature of relay 91 to segment 2 of the transmitter ring 58. 'In asimilar manner negative battery will be extended through segments 3 and5 or" ring 45to the windings of polar relays 92 and 94 and negativebattery will be extended to segments 3 and 5 of transmitting ring 58.Also, positive" battery will be extended through segments 4 and 6 ofring 45 to the windings of polar relays 92 and 94 and positive batterywill be extended to segments 4 and 6 of the transmitting ring 58.

lVhen brush 41 Wipes over the rest-start segment of ring 45 the restimpulse is received by the receiving relay 87. This impulse is negativeand causes the armature 96 of receiving relay 87 to be thrown againstthe contact 98 extending negative battery over the rest-start segment ofring 45 and over the conductor 104 to the winding of start magnet 50,but since the other end of the winding is also connected to negativebattery, the magnet 50 remains de-energized. Its armature will lie inthe path or the brush arm 40 causing this arm to come to rest on therest-start segment. It will be recalled that the auxiliary circuit forthe receiving start magnet 50 was opened at armature 102 of relay 88when the brush 44 moved off the segment 15 of ring'48. Thus it will beevident that the auxiliary circuit for magnet 50 is open before thebrush 41 reaches the segment 1' of ring 45.

When the brushes 43 and 44 wipe over the segments 11 and'12,respectively, positive battery is extended over these brushes andsegments and over wire 107 to the transmitting start magnet 60,energizing this magnet to release the brush arm 55 of the transmittingdistributor. Inasmuch as the arm 55 of the transmitting distributorstarts rotating later in the cycle than the start of brush arm 40,sufiicient time is provided for operation of each polar relay 90, 91,etc. before retransmission of the impulse stored up by said relay. Asthe brush 56 rotates, it comes first into engagement with the startsegment on ring 58, extending positive battery, which is. permanentlyconnected to the start segment,

over brush 56. brush 57, ring 59, conductor 108 and through the windingof transmitting relay 89, operating this relay to repeat apositive startimpulse over the conductor 111 leading to the local ticker or printer orto remote apparatus. The brush 56 then moves onto the segment 1 and asit wipes over the segment 1, a negative impulse is extended fromnegative battery over contact 115 of polar relay 90, and over thearmature of relay 90, segment 1 of ring 58, brush 56, brush 57, ring 59,conductor 108 and through the winding of transmitting relay 89 toground. Negative current flowing through winding of relay 89 operatesthe armature 109 into en-' gagement'with contact 112 extending anegative impulse over the line 111.

' Similarly, as. the brush 56 wipes over the segments 2 to 6, inclusive,circuits previously prepared bythe polar relays 91 to 95, inclusive,are. completed, and impulses are transmitted through the winding ofrelay 89 and'repeated thereby over the line 111, the polarityof theseimpulses depending upon taneously.

the positions of the armatures of the polar relays. The brush 56 thenarrives on the rest segment of ring 58 and is stopped thereon due to theengagementof the brush arm by the armature of magnet 60. During theinterval when brush 56 is in engagement with the rest segment, negativebattery, which is permanently connected to the rest segment, is extendedover the brush 56, brush 57, ring 59, conductor 108 and through thewinding of the transmitting relay 89 and repeated by this relay overline 111.

It will be noted that in the apparatus of Figure 2, the segments 1 to 6,inclusive, on the receiving ring 45 are short as compared with thesegments 1 to 6, inclusive, on the transmittingring 58. The timingrelation between the rotation ofbrush 41 and the incoming impulses issuch that brush 41 will be passing over the short segments on ring 45 asthe middle of each impulse is being received on the receiving relay 87.This relation is provided to take advantage of the fact that the middleof each impulse will probably be of the right polarity,whereas, thecrossover time or change of polarity between impulses is liable to bevariable. Thus, as long as thereiis enough left of each impulse tooperate receiving relay 87 and cause its armature to remain inengagement with one of its cont-acts long enough for the receiving brush41 to pass over the receiving segment'corresponding to that impulse, therepeater can be operated to retransmit the impulses as strong,well-shaped impulses.

The repeater of Figure 2 can be converted into a transmitter byswitching out the receiving equipment and switching in a trans mitterand its associated equipment. Any well-known means for performing thisswitching operation may be employed. Figure 3 shows the repeaterprepared to operate as a transmitter. In place of the receiving relay87, start relay 88 and the receiving distribntor, the equipmentcomprisesa tape c011- trolled transmitter 125, a cut-off relay 126, and thecommutator 34 which has already been described in connection with Figure1.

The tape controlled transmitter 125 is of the type wherein the contactscarried by the feelers 127 normally, that is, in their unselectedcondition, engage associated contacts 128 which contacts are allconnected to bus bar 129, and when in their selected position engageassociated contacts 130 which are all connected bus bar 131. Bus bar 129is connected directly to the brush 81 of commutator and bus bar 131 isconnected through winding 132 of cut-oil relay 126 to brush 79 ofcommutator 34. Brush 82 is connected to positive battery and brush 80 isconnected to negative battery. Segments 73 and 74 of the commutator areso arranged that they are engaged by their respective brushes simul-Accordingly negative battery will be applied to the bus bar 131 andpositive battery will be applied to bus bar 129 at,

the same time. I

The contactsof the feelers 127 of the tape controlled transmitter 125are connected to the windings of polar relays90 to inclusive. It will beapparent from this arrangement that when the feelers 127 have beenpositioned in accordance with perforations in the tape, those feelerswhich engage contacts 130 on bus'bar 131 will'extend negative battery tothe windings of their associated polar relays and those feelers-whichengage contacts 128 on bus bar 129, will extend positive battery to thewindings of their associated polar relays. Accordingly the arma tures ofthe polar relays are thrown to the right or left in accordance with theperform tiens in the tape. Y

The cut-0E relay 126 has in addition to the Winding 132, a winding 133which is arranged to oppose the efi'ect of the winding 132 but which isineffective to operate the established for the winding 132 providing oneor more of the feelers 127 is in engagement with the contacts'130 on thebus bar 131. Assuming that the uppermost feeler127 is in engagementwithitsassociated contact 130 on busbar 131, when segment 73 engages brushes79 and 80, the circuit will, extend from negative battery, over lowresistance ,135, brush80, segment 73, brush 79, winding 132, bus bar131, uppermost contact 130'and feeler 127 and through the winding of thepolar relay 95 to ground. Negativecurrent flowing through the winding132 will operate armature 134 of relay 126 into engagement with thecontact 137 thereby extending positive battery over contact 137 andarmature 134 to start segment'on'ring 58.

When segment 76 engages the brushes 85 and 86, an energizing circuit isestablished for the sending start magnet 60, this circuit extending frompositive battery over the brush 86, segment 76, brush 85, conductor 107and through the winding of magnet 60 to ground. As will be evident fromFigure 3, the position of the segment 76 on the 00111 mutator is suchthat this circuit is established a short time after the circuits throughsegments 73 and 74 are established. Energization of start magnet 60releases the brush arm 55 in the manner already described, and,

as the brush arm rotates, the circuits pre-' 7 pared by thepolar relays90 to 95,inclusive, arecompleted and impulses transmitted in sequence totransmitting relay 89 as described in connection with Figure 2. Sincethe brush 56 was initially resting on the rest segment, as in theprevious case, the start impulse will be the first impulse to betransmitted and so on through the other impulses of the completecharacter terminating on the rest segment.

After a selection has been made in the tape controlled transmitter 125and stored up in the bank of polar relays 90 to 95, inclusive, it

is necessary to step the perforated tape in the transmitter 125 andprepare it for the next selection. To this end a circuit is completedthrough the segment 72 of the commutator 34 and through the steppingmagnet 138, the circuit extending from positive battery over brush 78,segment 72, brush 77 and through the winding of magnet 138 to ground.Positive current flowing through magnet 138 energizes this magnet tostep the tape in the transmitter and thus preparing it for the nextselection. The energizing circuit for the magnet 138 is so timed that itis established after the circuits through segments 7 3'and 74 of thecommutator 34 have been opened.

I As previously described in connection with Figure 2, when the brush 56wipes over the start segment on ring 58, a positive impulse istransmitted over the line 111 to a printer or to remote receivingapparatus. To obtain this positive impulse the armature 134 of thecut-off relay 126 must be in engagement with the contact 137 of therelay 126. This engagement is effected when winding 132 of the relay 126is energized but in order to energize winding 132 at least one feeler127 must be in engagementwith its associated contact on bus bar 131. Itfollows, therefore, that if a particular code combination does notinclude marking impulses, as in the case where a blank space occurs inthe tape, there will be no feelers in engagement with contacts on busbar 131, winding 132, will be de-energized, armature 134 will be inengagement with contact 139 and a negative impulse will be transmittedover the start segment through the winding of relay 89 which will repeata negative impulse over the line 111. This negative impulse will notstart the apparatus at the receiving end, but the first positive impulsetransmitted over the line 111 will start that apparatus. Obviously thenthe apparatus at the receiving end will be out of phase with theapparatus at the transmitting end. To prevent this undesirable resub thewinding 133 and its circuit including the segment 75 on the commutatorare provided. This winding performs two functions, first, it prevents astart impulse from being transmitted when there is a blank space in thetape and second, applies negative battery to all of the segments of thetransmitting ring 58; Both of these functions are performed by the mereswitching of the armature 134 of relay 126 into engagement with contact139. The action of winding 132 will now be described.

When a blank space occurs in the tape all of the feelers 127 are inengagement with contacts 128 of bus bar 129 and the circuit whichextends from negative battery, through low resistance 135, brush 80,segment 73, brush 79 and through winding 132 to bus bar 131, isincomplete, so that winding132 remains de-energized. When the segment 75engages the brushes'83 and 84, an energizing circuit is established forthe winding 133 of the relay 126. This circuit extends from positivebattery over brush 84, segment 75, brush 83 and through the winding 133to ground. Positive current flowing through the winding 133 of thecut-off relay 126 causes the armature 134 thereof to be thrown intoengagement with contact 139.

Engagement of armature 134 with contact 139 extends negative batteryover contact 139 and armature 134 to the left-hand contacts of polarrelays 90 to 95, inclusive, and also to the start segment on thetransmitting ring 58. Consequently when the brush arm 55 is released,and brush 56 operates over the transmitting ring 58, every impulsetransmitted over the line 111 will be negative. Since a positive impulseis required to start the apparatus at the receiving end the saidapparatus will be prevented from starting.

In the following description of the operation of the embodiment shown inFigure 3, it will be assumed that the character Y is to be transmittedand that preceding the character Y there is a blank space in the tape.Accordingly the armature 134 of, cut-oil relay 126 is on its right-handcontact 139 and as the segment 72 of the commutator 34 moves intoengagement with brushes 77 and 78 the stepping magnet 138 is energizedand operates the tape-stepping mechanism to step the tape. Feelers 1, 3and 5 will be selected and will move into engagement with contacts onthe bus bar 131. Feelers 2, 4 and 6 will be unselected and will remaininengagement with contacts on bus bar 129. As the commutator 34 rotates,segment 75 will engage brushes 83 and 84 establishing a circuit for thewinding 133 of the cut-off relay 126. The efi'ect of energization ofwinding 133 will be to maintain the armature 134 of relay 126 inengagement with its contact 139. Immediately thereafter segments 7 3 and74 engage their respective brushes so that negative battery will beapplied through coil winding 132 to the bus bar 131 and positive batterywill be applied to the bus bar 129. The magnetic effect of the winding132 dominates that of winding 133 as above described and succeeds byreason of its later application so that the armature 134 of relay 126 isthrown into engagement with its contact 187. This applies positivebattery to the left-hand contacts of the polar relays to 95, inclusive,and also to the start segment'on ring 58. The windings of polar relays90, 92 and 94 will be energized by negative current from bus bar 131 andthe armatures of these relays will be thrown into engagement with theright-hand contacts. The windings of relays 91, 93 and 95 will beenergized by positive current from bus bar-129 and the armatures ofthese relays will be thrown into engagement with left-hand contacts.Thus, the selection of the character Y is stored in the polar relays 90to 95, inclusive.

As the connnutator 34 rotates, the segment 7 6 will engage the brushes85 and 86 energizing the sending start magnet 60 which releases thebrush arm 55 for rotation. The brush 56 wipes over the start segmenttransmittin g a positive impulse over the conductor 111 which starts theremote receiving apparatus into operation. The brush 56 then wipes overthe segments 1 to 6, inclusive, in succession transmitting impulses overthe segments to'the conductor 111, and finally the brush 56 will come torest on the rest segment of the,

ring 58. It will be clear that as the brush 56 wipes over the segments1, 3 and o negative impulses will be applied to the transmitting relay89 and over the conductor 111, and as the brush 56 wipes'over thesegments 2, 4 and 6 positive impulses will .be applied to thetransmitting relay 89 and over the conductor 111. Thus, the characterYis transmitted.

We have referred in the above description to a transmitter of the tapecontrolled type for purposes of illustration but it is evident thatother types of transmitters may be employed, such for instance asstoring transmitters.

1. In a start-stop telegraph system,-a'receivingdistributor, meansresponsive to incoming impulses tor starting said distributor intooperation, a local distributor 'and means controlled by said localdistributoroperating as an auxiliary to said starting means for controlling the starting of the receiving distributor. I

2. In a start-stop telegraph system, a receiving distributor, means forcontrolling the starting of said distributor. plurality of relayscontrolled by. said distributor. a transmitting distributor controlledby said relays ano a local distributor for controlling the starting or"the receiving distributor and the transmitting distributor. V a

3. In a start-stop telegraph system, a re ceiving distributor, apluralityjof relays controlled by said receiving distributor, atransmitting distributor controlled by said relays and a localdistributor controlling the phase relation between the receivingdistributor and the transmitting distributor.

l. Ina start-stop telegraph system, a receiving distributor, a magnetfor controlling the starting of said distributor, said magnet beingcontrolled by the distributor, auxiliary means for controlling saidmagnet and a local distributor controlling said auxiliary means.

5. In a start-stop telegraph system, a receiving relay responsive toincoming impulses, a receiving distributor for distributing the impulsesreceived by said relay, a plurality of polar relays controlled by saidreceiving distributor for repeating the impulses, a transmittingdistributor for distributing the impulses repeated by said polar relays,an d a transmitting relay responsive to the impulses distributed by thetransmitting distributor for repeating the same to a remote station.

6. In a start-stop telegraph system, a receiving relay responsivetoincoming impulses, aplurality of polar relays, means controlled bysaidreceiving relay for distributing the incoming impulses to the polarre lays, a transmit-ting relay for transmitting the impulses to a remotepoint and a trans mitting distributor for distributing the impulsesreceived by said. polar relays to said transmitting relay.

7. In a start-stop telegraph system,a rotary distributor, a magnet forcontrolling the starting of said distributor, an energizing cir-' cuitfor said magnet controlled by the distributor and an auxiliaryenergizing circuit for said magnet, said auxiliary circuit beingindependent or said distributor.

8; ln start-stop telegraph system, a rota-ry distributor, a magnet forcontrolling the starting of said distributor, an energizing circuit forsaid magnet controlled by the distributor, an. auxiliary energizingcircuit for said magnet, said auxiliary circuit being independent-ofsaid distributor, and a local distributor operating in synchronism withsaid receiving distributor and controlling said auxiliary circuit.

9. In a start-stop telegraph system, a rotary distributor, a magnet forcontrolling the starting of saiddistributor, an energizing circuitforsaid magnet-controlled by the distributor, an auxiliary energizingcircuit for said magnet, said auxiliary circuit being independent ofsaid distributor, a relay for controlling said auxiliary circuit andmeans operating in synchronism with said distributor for controllingsaid relay.

10. In a start-stop telegraph system, a tape controlled transmitter, aplurality of polar relays controlled by said transmitter, a transmittingdistributor and continuously operatsequence control means forcontrolling the operation of said tape controlled transmitter and saidtransmitting distributor. I

11. In astart-stop telegraph system, a plurality of tape controlledelements, a plurality of relays controlled by said elements, means itioiis

for transmitting a code combination of impulses in accordance with theoperation of said relays, and a continuously operating commutator forcontrolling the starting of said last mentioned means.

12. In a start-stop telegraph system, a plurality of tape cont-rolledelements adapted to be positioned in accordance with perforations in atape, a distributor for transmitting impulses over a line in accordancewith the positions of the tape controlled elements, a continuouslyrotating commutator, means controlled by said commutator for extending astart impulse to the start segment of the distributor and additionalmeans controlled by the commutator for preventing the transmission of astart impulse by said distributor when the tape-controlled elements areall in predetermined position.

13. In a start-stop telegraph system, a plurality of tape controlledelements adapted to occupy one of two positions in accordance withperforations in a tape, a plurality of polar relays adapted to beoperated in accordance with the positions of said tape controlledelements, a distributor for transmitting positive or negative impulsesin accordance with the operation of the polar relays,

a continuously rotating commutator, said commutator controlling thestarting of said distributor, a cut-oil relay having a plurality ofwindings controlled by said commutator, one of said windings controllingthe transmission of a start impulse by the distributor and the other ofsaid windings operating to prevent the transmission of a start impulseby the distributor when the said tape controlled elements occupypredetermined positions.

14. In a start-stop telegraph transmitter, a plurality of tapecontrolled elements adapted to occupy one of two positionsin accordancewith perforations in a tape, a rotary distributor for transmittingimpulses over a line in accordance with the positions of the tapecontrolled elements, said distributor comprising a rest segment, a startsegment, and a plurality of code segments, means for applying apredetermined potential to the start segment of the distributor andmeans for applying a potential of opposite polarity to all of thesegments of the distributor under a predetermined condition.

15. In a start-stop telegraph system, a plurality of tape-controlledelements adapted to occupy oneof two positions in accordance withperforations in a tape, a distributorfor transmitting impulses over aline in accordance with the positions occupied by the tape controlledelements, said distributor comprising a start se ment, a plurality ofcode segments and a rest segment, an electric relay for applying a startimpulse condition to the starting segment under predetermined conditionsin the tape and for applying a difi'erent impulse condition to the startsegment under other predetermined conditions in the tape.

16. In a start-stop telegraph system, a plurality of tape controlledelements adapted to occupy one of two positions in accordance withperforations in a tape, a distributor for transmitting impulses over aline in accordance with the positions occupied by the tape controlledelements, said distributor comprising a start segment, a plurality ofcode segments and a rest segment, an electric relay for applying a startimpulse to the start segment under predetermined conditions in the tapeand for applying a difierent impulse to the start segment underpredetermined other conditions in the tape, and continuously rotatingmeans for controlling said relay.

17. In a start-stop telegraph system, a plurality of tape controlledelements adapted to occupy one of two positions in accordance withperforations in a tape, a distributor for transmitting impulses over aline in accordance with the positions occupied by the tape controlledelements, said distributor comprising a start segment, a plurality ofcode segments and a rest segment, an electric relay for applying a startimpulse to the start segment under predetermined conditions in the tapeand for applying a diiferent impulse to the start segment underpredetermined other conditions in the tape and means for timing theoperation'of the distributor and the relay and for controlling thestepping of p the tape.

18.'In a start-stop telegraph system, a transmitter, a plurilaty ofrelays controlled by said transmitter, a distributor for transmittingpositive or'negative impulses in accordance with the operation of saidrelays, and continuously operating sequence control means forcontrolling the operation of said transmitter and said distributor.

19. In a start-stop telegraph system, a plurality of contacts'adapted tobe positioned in accordance with a predetermined coding, a plurality ofrelays controlled by the position of said contacts, means fortransmitting a code combination of impulses in accordance with theoperation of said relays, and a continuously operating commutator forcontrollin g the starting of said last mentioned means.

20. In a start-stop telegraph system, a transmitter having a pluralityof contacts adapted to be positioned in accordance to a predeterminedcoding, a plurality of relays controlled by the position of saidtransmitter contacts, a transmitting distributor, and con tinuouslyoperating sequence control means for controlling the operation of saidtransmitter and said distributor.

21. In a start-stop telegraph system, a plurality of contacts adapted tobe positioned in accordance with a predetermined coding,

a line in accordance with the positions .00- cupied by said contacts,said distributor comprising a start segment, a plurality of codesegments and a rest segment, a relay for applying a start'impulse tosaid start segment under predetermined positioning of said contacts andfor applying a difierent'impulse to said start segment under otherpredetermined positioning of said contacts.

In testimony whereof we affix our signa- ROBERT F. DIRKES.

JAMES NANDERSON, JR.

